CVE-2023-33974: RIOT-OS vulnerable to Race Condition in SFR Timeout

Severity: medium (CVSS 5.9 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.7% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2023-05-30 · updated 2026-06-17
Weakness: CWE-362

Description

RIOT-OS, an operating system for Internet of Things (IoT) devices, contains a network stack with the ability to process 6LoWPAN frames. In versions 2023.01 and prior, an attacker can send multiple crafted frames to the device to trigger a race condition. The race condition invalidates assumptions about the program state and leads to an invalid memory access resulting in denial of service. This issue is patched in pull request 19679. There are no known workarounds.

Affected products

RIOT-OS RIOT: through 2023.01

References

https://github.com/RIOT-OS/RIOT/blob/f41b4b67b6affca0a8b32edced7f51088696869a/sys/net/gnrc/network_layer/sixlowpan/frag/sfr/gnrc_sixlowpan_frag_sfr.c#L1717
https://github.com/RIOT-OS/RIOT/blob/f41b4b67b6affca0a8b32edced7f51088696869a/sys/net/gnrc/network_layer/sixlowpan/frag/sfr/gnrc_sixlowpan_frag_sfr.c#L509
https://github.com/RIOT-OS/RIOT/blob/f41b4b67b6affca0a8b32edced7f51088696869a/sys/net/gnrc/network_layer/sixlowpan/frag/sfr/gnrc_sixlowpan_frag_sfr.c#L617
https://github.com/RIOT-OS/RIOT/blob/master/sys/net/gnrc/network_layer/sixlowpan/frag/sfr/gnrc_sixlowpan_frag_sfr.c#L1586
https://github.com/RIOT-OS/RIOT/blob/master/sys/net/gnrc/network_layer/sixlowpan/frag/sfr/gnrc_sixlowpan_frag_sfr.c#L404
https://github.com/RIOT-OS/RIOT/commit/31c6191f6196f1a05c9765cffeadba868e3b0723
https://github.com/RIOT-OS/RIOT/pull/19679
https://github.com/RIOT-OS/RIOT/security/advisories/GHSA-8m3w-mphf-wxm8
https://github.com/RIOT-OS/RIOT/blob/f41b4b67b6affca0a8b32edced7f51088696869a/sys/net/gnrc/network_layer/sixlowpan/frag/sfr/gnrc_sixlowpan_frag_sfr.c#L1717
https://github.com/RIOT-OS/RIOT/blob/f41b4b67b6affca0a8b32edced7f51088696869a/sys/net/gnrc/network_layer/sixlowpan/frag/sfr/gnrc_sixlowpan_frag_sfr.c#L509
https://github.com/RIOT-OS/RIOT/blob/f41b4b67b6affca0a8b32edced7f51088696869a/sys/net/gnrc/network_layer/sixlowpan/frag/sfr/gnrc_sixlowpan_frag_sfr.c#L617
https://github.com/RIOT-OS/RIOT/blob/master/sys/net/gnrc/network_layer/sixlowpan/frag/sfr/gnrc_sixlowpan_frag_sfr.c#L1586

Get alerted when CVE-2023-33974 or the next vulnerability affects your stack